18,634 research outputs found
2003 Annual Update to "...and Justice for All": DVRPC's Strategy for Fair Treatment and Meaningful Involvement of All People
This update is based on previous work performed at DVRPC on the topic of Environmental Justice, namely, "...and Justice for All": DVRPC's Strategy for Fair Treatment and Meaningful Involvement of All People (September 2001) and Annual Update to "...and Justice for All" (September 2002). This report further updates and refines the quantitative methodology, using Year 2000 U.S. Census data
Random Field Ising Model In and Out of Equilibrium
We present numerical studies of zero-temperature Gaussian random-field Ising
model (zt-GRFIM) in both equilibrium and non-equilibrium. We compare the
no-passing rule, mean-field exponents and universal quantities in 3D (avalanche
critical exponents, fractal dimensions, scaling functions and anisotropy
measures) for the equilibrium and non-equilibrium disorder-induced phase
transitions. We show compelling evidence that the two transitions belong to the
same universality class.Comment: 4 pages, 2 figures. submitted to Phys. Rev. Let
Anatomy and Histology of the Male Reproductive Complex of the Onion Maggot Fly, \u3ci\u3eDelia Antiqua\u3c/i\u3e, (Diptera: Anthomyiidae) Including Some Comparisons With \u3ci\u3eD. Platura\u3c/i\u3e and \u3ci\u3eD. Radicum\u3c/i\u3e
In Delia antiqua (Meigen) (Diptera: Anthomyiidae), the male reproductive complex is composed of a pair of testes, paired vas deferens connecting the testes to the anterior ejaculatory duct, and a pair of paragonial (accessory) glands. Each D. antiqua paragonial gland consists of a single layer of secretory epithelial cells surrounded by a thin sheath of muscle tissue. The paragonial cells appear to be largely homogeneous in form, however a minor number of cells exhibit unique staining characteristics distinct from the main cells of the gland. This is preliminary evidence for a secondary cell type as has been found for Drosophila and Aedes paragonial glands. In contrast to the testis and vas deferens, where most of the growth occurs during the pupal stage, the D. antiqua paragonial glands expanded markedly due to secretory accumulation during the first days of adult life. Based on histochemical analyses, the paragonial secretion contained abundant protein, with evidence of glycoprotein. The reproductive complex in all three Delia species (D. antiqua, D. radicum (Bouche) and D. platura (Meigen)) appears similar, with the exception of size differences and timing of paragonial secretory accumulation and sperm maturation. Paragonial glands of D. radicum were the largest in both length and width, and only this species possessed abundant sperm upon eclosion. Of the three species, D. radicum appears most capable of mating immediately after eclosion based on the histology of its reproductive complex, which is consistent with biochemical and behavioral observations made earlier in this laboratory
An Allometric Study of the Boxelder Bug, \u3ci\u3eBoisea Trivittata\u3c/i\u3e (Heteroptera: Rhopalidae)
An allometric study was conducted on the boxelder bug, Boisea trivittata, to confirm the number ofinstars and to identify characteristics most useful for rapid instar identification of field samples. Analysis of field populations collected throughout the 1990-92 seasons indicated that there were five instars, clearly defined on the basis of size and the presence of wing pads. This finding is in contrast with the only other published study on stages of the boxelder bug, which claims there are six nymphal instars.
Size data gathered from field populations were substantiated by laboratory growth studies. Head width and/or second antennal segment length were identified as the most useful parameters for instar identification
Abundance and distribution of California sea lions (Zalophus californianus) in central and northern California during 1998 and summer 1999
The abundance and distribution of California sea lions
(Zalophus californianus) in central and northern California was studied to allow future evaluation of their impact on salmonids, the ecosystem, and f isheries. Abundance at-sea was estimated by using the strip transect method from a fixed-wing aircraft with a belly viewing port. Abundance on land was estimated from 126-mm-format aerial photographs of animals at haulouts between Point Conception and the
CaliforniaâOregon border. The sum of these two estimates represented total abundance for central and northern
California. Both types of survey were conducted in MayâJune 1998, September 1998, December 1998, and July 1999. A haulout survey was conducted in July 1998. The greatest number of sea lions occurred near Monterey Bay and San Francisco Bay for all surveys. Abundance was high in central
and northern California in 1998 when warm water from the 1997â98 El Niño affected the region and was low in July 1999 when cold water La Niña conditions were prevalent.
At-sea abundance estimates in central and northern California ranged from 12,232 to 40,161 animals, and haulout abundance was 13,559 to 36,576 animals. Total abundance of California sea lions in central and northern California was estimated as 64,916 in MayâJune 1998, 75,673 in September 1998, 56,775 in December 1998, and 25,791 in July 1999. The proportion of total abundance to animals
hauled-out for the four complete surveys ranged from 1.77 to 2.13, and the mean of 1.89 was used to estimate a total abundance of 49,697 for July 1998. This multiplier may be applicable in the future to estimate total abundance of California sea lions off central and northern California
if only the abundance of animals at haulout sites is known
No-passing Rule in the Ground State Evolution of the Random-Field Ising Model
We exactly prove the no-passing rule in the ground state evolution of the
random-field Ising model (RFIM) with monotonically varying external field. In
particular, we show that the application of the no-passing rule can speed up
the calculation of the zero-temperature equilibrium curve dramatically.Comment: 7 pages, 4 figure
Transforming mesoscale granular plasticity through particle shape
When an amorphous material is strained beyond the point of yielding it enters
a state of continual reconfiguration via dissipative, avalanche-like slip
events that relieve built-up local stress. However, how the statistics of such
events depend on local interactions among the constituent units remains
debated. To address this we perform experiments on granular material in which
we use particle shape to vary the interactions systematically. Granular
material, confined under constant pressure boundary conditions, is uniaxially
compressed while stress is measured and internal rearrangements are imaged with
x-rays. We introduce volatility, a quantity from economic theory, as a powerful
new tool to quantify the magnitude of stress fluctuations, finding systematic,
shape-dependent trends. For all 22 investigated shapes the magnitude of
relaxation events is well-fit by a truncated power law distribution , as has been proposed within the context of plasticity
models. The power law exponent for all shapes tested clusters around
1.5, within experimental uncertainty covering the range 1.3 - 1.7. The
shape independence of and its compatibility with mean field models
indicate that the granularity of the system, but not particle shape, modifies
the stress redistribution after a slip event away from that of continuum
elasticity. Meanwhile, the characteristic maximum event size changes by
two orders of magnitude and tracks the shape dependence of volatility. Particle
shape in granular materials is therefore a powerful new factor influencing the
distance at which an amorphous system operates from scale-free criticality.
These experimental results are not captured by current models and suggest a
need to reexamine the mechanisms driving mesoscale plastic deformation in
amorphous systems.Comment: 11 pages, 8 figures. v3 adds a new appendix and figure about event
rates and changes several parts the tex
Understanding employment systems from a gender perspective: pitfalls and potentials of new comparative analytical frameworks
Economic globalization, welfare state transformation as well as political and social change on national and supranational level impact on national labor markets in advanced societies in complex ways. From a gender perspective, these dynamics of change entail deregulation as well as re-regulation of employment systems and at the same time are triggered by shifts in gender relations. Addressing this complexity poses challenges to scholarly research comparing employment systems and systemizing cross-national variations of labor market regimes which tend to neglect gender relations as a relevant factor of change. This context sets the framework for our question on how ongoing changes in employment systems and in gender relations are taken up in recent scholarship. We focus on three approaches prominent in the mainstream scholarly debate which address the current state of employment systems in advanced economies in comparative perspective spanning from political economy to micro economics and economic sociology, namely the Varieties of Capitalism (VOC) approach (Hall/Soskice 2001), Marsden's micro-economic theory of employment systems (1999) and Fligstein's work 'The architecture of markets' (2001). The approaches differ in the assignment of agency (to firms, employees and the state) as well as in the assessment of the role of educational institutions for shaping employment systems. They thus dispose of different pitfalls and potentials for analyzing the gendered character of change of employment systems. -- Unter dem Einfluss von Globalisierung, Wohlfahrtsstaatstransformation und politischen und gesellschaftlichen UmbrĂŒchen sind nationale ArbeitsmĂ€rkte in fortgeschrittenen Marktökonomien erheblichen VerĂ€nderungen ausgesetzt. In geschlechtssensibler Perspektive wird deutlich, dass hier nicht nur Deregulierung von BeschĂ€ftigung sondern auch Re- Regulierung eine Rolle spielt, ebenso wie Arbeitsmarktdynamiken auch durch VerĂ€nderungen im GeschlechterverhĂ€ltnis beeinflusst sind. Diese KomplexitĂ€t des Wandels stellt eine Herausforderung fĂŒr die vergleichende Arbeitsmarkt- und Wohlfahrtsstaatsforschung dar, in deren Typisierung von Arbeitsmarktregimes GeschlechterverhĂ€ltnisse nur begrenzt BerĂŒcksichtigung finden. Vor diesem Hintergrund fragen wir, wie in einschlĂ€gigen neueren AnsĂ€tzen zur Analyse von ArbeitsmĂ€rkten Wandel von BeschĂ€ftigungssystemen und GeschlechterverhĂ€ltnissen konzipiert wird. Im Mittelpunkt stehen drei prominente komparatistisch ausgerichtete Konzepte: der polit-ökonomische Ansatz âVarieties of Capitalismâ (Hall/Soskice 2001), die mikro-ökonomische Theorie von BeschĂ€ftigungssystemen von David Marsden (1999) und Neil Fligsteinâs wirtschaftssoziologischer Ansatz âThe architecture of marketsâ (2001). Wie die Ergebnisse zeigen, unterscheiden sich die AnsĂ€tze in der Identifikation von relevanten Akteuren (Betriebe, BeschĂ€ftigte, Staat) ebenso wie in der Rolle, die Ausbildungsinstitutionen fĂŒr die Strukturierung von ArbeitsmĂ€rkten zugeschrieben wird. Damit ergeben sich fĂŒr die Analyse von geschlechtsspezifischen Aspekten von BeschĂ€ftigung unterschiedliche blinde Flecken und Erkenntnispotentiale.
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